Lecture 1 Flashcards
Prokaryote
Unicellular organism relatively simple cell structure

Eukaryote
Compartmentalized cell structure bounded by intracellular membranes, uni or multicellular
Eubacteria
True bacteria
Archaea
Ancient bacteria
Nucleus
Separates DNA from other cellular components
Histones
Special class of proteins that form tightly packed chromosomes
Viruses
NOT A CELL
IT
IS
NOT ALIVE
**Homolugous Pair **
A pair of genes that code for the same trait
Diploid
Carry two sets of genetic information
Haploid
Single set of chromosomes
Telomers
Natural ends/tips of a linear chromosome
Origin of Replication
Sites where DNA replication
Interphase
Period between cell divisions, DNA is synthesized includes several checkpoins
**M phase **
Mitosis
Prophase
Chromosomes become visible, chromosomes condense, mitotic spindle forms
Prometaphase
Nuclear membrane disintefrates, spindle microtubules attach to chromatids
Telophase
Chromosomes arrive at spindle poles. Nuclear membrane re-forms, chromosomes relax
Anaphase
Sister Chromatids separate and move towards opposite poles
Metaphase
Chromosomes line up on metaphase plate
Meiosis
Sexual Reproduction, cuts chromosome # in half
**Fertilization **
Two haploid gametes fuse and restore chromosome number to its original diploid value
**Prophase I **
Divided into 5 stages:
- Leptotene - Chromosomes contract and become visible
- Synapsis-Close pairing asociation
- bivant/tetrad - homologouse pair of chromosomes consisting of 4 chromatids
- Pachytene- chromosomes shorter and thicker, forms three part synaptohemal complex between homologous chromosomes
- Diplotine
- Diakinesis
Crossing Over
Takes place in prophase I (diakenisis) at the chrosmata
Chiasmata
Where two sister chromatids connect to exchange fenetic information